Good question! William is correct, @Douglas Wever; however, not all search engine robots are created equal. The good ones find all the new material or topics or reviews and add links to those on the big search engine sites like Google, Yahoo!, Bing... And then there are the not so good robots...generally from countries and businesses that specialize in hacking sites. At one point we were seeing as many if not more robots than members & visitors! Many of those are looking for ways to produce spam and don't generate any valuable links to material on our site or anyone's site. Our programmer has updated filters to block those robots. We can see where traffic is coming from by looking at the site analytics and that info is broken down by people, other sites and the robots. So, the dozen or so typical robots is A-OK and nothing to worry about.